Piet Hein was brilliant! He began writing his Grooks as a member of the Danish underground during World War II, so some of them have a double meaning that was apparently largely lost on the Nazi occupiers.
Below, a sample of his thoughts on progress, taken from Grooks (Copenhagen: Borgens Billigbøger 85, 1966, 1989) and Grooks II (Borgens Billigbøger 84, 1973, 1989). I don't know who did the translations into English, but they work remarkably well. Interestingly, he dedicated the second book to Charles Chaplin. Also, the legalese reads, ""Grooks may not be set to music without the author's consent." I have to wonder what prompted that specific prohibition? Perhaps his Grooks in Music book, which apparently had eighteen Grook verses graced with facing music by Svend Asmussen, the late Danish swing violin virtuoso who died this year, age 100.